Hi all. I have some comments regarding multipath.conf. 1) Can someone point me to the latest version of the documentation? The following examples seem to show that the multipath(d) are not in sync with the man. a) polling_interval The man page and the comments in the multipath.conf say that the default value is 5, but when I execute "multipath -t" when I didn't specified the value in multipath.conf it says the polling_interval is 0. I don't even know what 0 means. Is "multipath -t" giving incorrect values? Is my reasonning wrong? Other? b) path_grouping_policy man says that the default is multibus. Red Hat Documentation ( http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/DM_Multipath/config_file_defaults.html ) says the default is Failover. c) prio man says default is none. Red Hat Documentation ( http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/DM_Multipath/config_file_defaults.html ) says the default is const. d) Why "prio emc" gives "sda: emc prio: query command indicates error", when I execute multipath -v2 -d with multipathd not running. And sda is even in the blacklist. e) If I have EMC Clariion Disk Array, should I use: "path_checker emc_clariion"? f) What is the correct getuid_callout: - /sbin/scsi_id -g -u -s /block/%n (As old EMC document says) - /sbin/scsi_id -g -u -s (As the man says) - "/lib/dev/scsi_id --whitelisted --device=/dev/%n" (As http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/DM_Multipath/config_file_defaults.html says.) g) There maybe more differences. I didn't check all. 2) Maybe this is not a question to this forum, but what are the correct defaults section in multipath.conf for a host (SLES 10) in a cluster (so quick failover), dual HBA to dual switch, with " # Emulex lpfc options options lpfc lpfc_nodev_tmo=3 lpfc_devloss_tmo=3 " in /etc/modprobe.conf. What do you think of: defaults { polling_interval 5 # max_polling_interval 4 udev_dir /dev verbosity 2 selector "round-robin 0" path_grouping_policy multibus getuid_callout /sbin/scsi_id -g -u -s /block/%n prio const # prio_callout mpath_prio_emc /dev/%n features 1 queue_if_no_path path_checker directio failback immediate # Previous one for a quick failover rr_min_io 1000 rr_weight priorities no_path_retry fail # Previous one for a quick failover # pg_timeout none user_friendly_names yes max_fds 8192 bindings_file "/etc/multipath_bindings" # Previous one for future compatibility and same partition has /root dev_loss_tmo 2 # Previous one for a quick failover fast_io_fail_tmo 1 # Previous one for a quick failover async_timeout 30 } Because of the first problem I prefer to define the parameters even if they are equal to the defaults values instead of not defining the parameters. Thanks in advance, TA. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
